Black azo dye and process of making same.



barren s'rarns Parana orrrcn.

KARL HAGEMANN AND orro S'IANGE, or LEYERKUSEN, NEAR cohoc'xn, GERMANY,ASSIGNORS ro FARBENFABRIKEX vonn. ram s; BAYER 00., or ELBERFELD,GERMANY, A CORPORATION or GERMANY,

BLACK AZO DYE AND PROCESS OF mAKiuG sA EQj newfand useful Improvementsin new A20 Dyes, of which the following is a specification. Y

e have discovered that the hitherto unknown 1 arylamino S naphtholsulfonic ac1dssuch as 1-phenylamino-S-naphthol-S- 6- or 4-6- disulfonicacid, l paraanisylamino 8 -naphthol-3-6-disulfonic acid, 1-betanaphthylamino-S-naphthol-d-sulfonic acid, or the likeconstitute valuablecomponents for the production of azo dyestuffs. These dyestuffs'j lare,obtained by combining the 1- arylamino S naphthol sulfonic acids withdiazo compounds, such as the diazo deriva tives of anilin,paranitranilin, naphthylamin, dichloranilin, anisidin, amidoazobenzene,amidophenols, amidophenol sulfonic acids, or the like.

he above mentioned 1 arylamino- 8 naphthol-sulfonic acids are obtainedby heating 1-amino-8-naphthol-sulfonic acids-such as1-amino-8-naphthol-36, 4-6, or 3-5- disulfonic acid, 1 amino- 8 naphtholl-sulfonic acid, or the likewith water and aromatic aniins orderivatives thereof, such as anilin, toluidin, anisidin, chloroanilin,naphthy amin, or the like. The condensation may also be carried out inthe presence of salts of aromatic amins or condensing agents.

The new dyestuffs obtained by the combination of diazo compounds withthe 1- arylamino-8naphthol-sulfonic acids are in the shape of theiralkaline salts dark powders soluble in water with from a red to blue toblack color; soluble in concentrated sulfuric acid with from a red toviolet to blue color and dying wool from acid-baths from violet to blueto black shades.

In carrying out the new process practically we can proceed as follows,the parts being by weight: In an autoclave three hundred and forty-oneparts of the monosodium salt of 1-amino-8-naphthol-3-o-disulfonic acidare heated with two hundred parts of anilin and one'thousand parts ofwater to 120 centigrade for forty-eight hours. After the Specificationof Letters Patent.

A lication filed March 28.1906. Serial No. 308,452.

m'on salt, filtered off, and dried. being dried and. ulverized, in theshape of its Patented Feb. 12,

, I addition of sodium carbonateto'the mass of the reaction the excessof "anilin is distilled 1 phenylamino 8'- naphthol 3 6 disulfonic acidis precipitated therefrom by the addition of common salt, filtered off,and dried. It is thus obtained in the shape of white needles easilysoluble in water and solublewith difficulty in alcohol. I

The process .is carried out in an analogous manner for the production ofother l-arylamino-8-naphthol-sulfonic, acids.

The preparation of the dyestuffs obtainable from the1-arylamino-S-naphthol-sulfonic acids is carried out in the usual waye.9., in the following manner, the parts being by weighti 13.8 parts ofparanitranilin are diazotized in the usual manner by means of sevenparts of sodium nitrite and the necessary quantity of hydrochloric acid.The diazo solution is then added while stirring to a solution of 39.6parts of 1-phenyl'amino-8- naphthol-36-disulfonic acid, which solutioncontains an excess of sodium carbonate. After some hours the formationof thedyestufi is complete. Theproduct of the reaction is heated for, ashort while, and the dyestuli is precipitated by the addition of com- Itis, after sodium salt a b ack powder soluble in. water with aviolet-black color and in concentrated sulfuric acid with a red color.By reduction with stannous chlorid and hydrochloric acidpara-phenylenediamin and l-phenylamino- 7-amino-Smaphthol-3-fidisulfonic acid is obtained. The new dyestuff dyes wool from acid-bathsdeep-black shades.

Instead of diazotized paranitranilin diazo compounds of other amins maybe used.

Having now described our invention and in what manner the same is to beperformed, what we claim as new, and desire to secure by Letters Patent,is V 1. The herein-described new azo dyestuifs obtainable by combiningdiazo compounds with 1-arylamino-8naphthol-sulfonic acids, whichdyestuffs are, after being dried and pulverized, in the shape of theiralkaline salts dark powders soluble in water, soluble in concentratedsulfuric acid with from a red to violet to blue color; and dyeing Wool.from acid-bat Lis l'mnrviolct to blue to black ,hades, substantiallyheroin-helorc described.

2. The herein-(lcscrihed new azo (lyest' iii', which can he obtained bycombining die-zotizecl paranitranilin with l-phenylamino-S- naphthol 36-disulfonic acid, which dyest ufl is, after being dried and pulverized,in

theshz pe 01 its sodium salt a black powder soluble in water Vi-U1 3violet-Black and. in concentrated slfilfuricacid with a red color;yiekling upon reduction with stannous chlorid and hydrochloric acidpara-phenylenediainin and I-phenylaininoJ-amino8;.m.ph--

thol 3 6 disulfonic acid and dyeing wool from acid-baths black shades,substantially as l1618lI1l')6l'()fii"(lCSClllJ( l.

In testimony whereof we have hereunto set our hands inthe presence oftwo subscmbing witnesses.

KARL HAGEMANN.-

